[LIR] Obey non-integral pointer semantics

Summary: See http://llvm.org/docs/LangRef.html#non-integral-pointer-type

Reviewers: haicheng

Reviewed By: haicheng

Subscribers: mcrosier, mzolotukhin, llvm-commits

Differential Revision: https://reviews.llvm.org/D32196

llvm-svn: 301238